Method and apparatus for measuring and feeding back channel information

A method for measuring and feeding back channel information and a corresponding apparatus are provided. In an embodiment the method includes determining, by a first network device, a first codebook from a first codebook set, wherein the first codebook set comprises at least two first codebooks, wherein a sub-vector Wx of each first codebook is formed by a zero vector and a non-zero vector, wherein vectors forming the Wx are associated with different groups of antenna ports, wherein each first codebook comprises at least one first sub-vector and/or at least one second sub-vector and wherein Va0 and Va1 are elements in the vector Va, and Vb0 and Vb1 are elements in the vector Vb and sending a codebook index to a second network device, wherein the codebook index is associated with the first codebook selected from the first codebook set.